[en] A digital ten-channel delayed pulse generator is described. The delay time for each channel is set individually within the 10^-6-10² s limits in decimal system with 1 mcs step. Accuracy and stability of time intervals between the delayed pulses are close to the corresponding quartz generator

[en] Mechanism of atom acceleration in x radiation flux at the expense of a pulse transmitted to the atom under a photoeffect from the internal shell is considered. It is ascertained that under the x-ray quantum energy E_γ >or approx.E_K (absorption K-edge energy) the atom is accelerated along radiation propagation trajectory and E_γ≥E_K the atom is accelerated in the opposite direction. A possibility of applying this effect for atom acceleration is considered for the first time. Formulae for acceleration rate are derived. The maximum possible acceleration rate performed for accelerated Ar atoms gives about 100 GeV/m under ∼2.7x10²³ W/cm² power flux. Such accelerator efficieny grows with the increase of accelerated atom finite energy ∼√E. Under Ar atom acceleration up to 1 GeV the accelerator efficiency is ∼10%. Difficulties related to the way of this acceleration technique realization are discussed. A possibility of realizing the described acceleration mechanism under the natural conditions near x-ray astrophysical sources and its effect on the substance distribution in the cosmic space is underlined. Atom selection by mass occuring near such sources (the light atoms are accelerated towards the source and heavy ones-backwards) can be one of the reasons for relative enrichment of cosmic radiation by heavy elements and star enrichment by light elements (star fuel). A possible process of a star formation near the X-ray source is described

[en] The parametric X-ray radiation (PXR) is a new type of monochromatic, polarized, directed, tunable radiation arising in the vicinity of Bragg directions of a crystal when relativistic particles are passing through the crystal. For the last ten years the PXR properties have been intensively investigated experimentally at moderate incident electron current. In this paper we consider main properties of PXR as a new source of a powerful monochromatic X-ray beam, excited by short high-current electron bunch in a single crystal. It is shown, that using a PXR, one can obtain X-ray beam power of about MW/sr during a short period of time at moderate incident electron energy. Experimental setup for generating pulsed PXR beam is suggested, and possibilities for application of pulsed polarized monochromatic X-ray beams are discussed

[en] The results of measurements of absolute differential yield of parametric X-ray radiation (PXR) in thin single crystal are presented for the first time. It has been established that the experimental results are in good agreement with theoretical calculations according with kinematical theory. The influence of density effect on PXR properties is discussed. (author). 19 refs., 7 figs

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[en] A review on some of the recent developments in investigations of parametric X-ray radiation (PXR) is presented. Some perspectives for PXR applications as a source of linearly polarized, quasi monochromatic, smoothly tunable X-ray beams for energies from few to several hundred keV are described. (author)

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[en] Results of experimental investigation into spectral-angular characteristics of parametric X radiation (PXR) of electrons with E_e=25 MeV in a thin silicon monocrystal are considered. Comparison of the measured PGR energy orientation dependence and coherent radiation energy calculation allows one to make a conclusion about the recorded radiation coherence and the minority of contribution to spectra by bremsstrahlung diffracted in the crystal. PXR spectral line width measured agrees with the calculation according to the formula, taking account of real interval of angle of radiation recording by a detector. Effect of a series for PXR similar to series effect for coherent bremsstrahlung is considered. The form of the PXR intensity orientation dependence measured agrees with the intensity calculation by PXR kinematic theory. 14 refs.; 3 figs

No abstract available